Gas delivery system with constant overpressure relative to ambient to system with varying vacuum suction

ABSTRACT

A system operating in an environment having an ambient pressure, the system comprising: a reactor configured to combine a plasma stream, powder particles and conditioning fluid to alter the powder particles and form a mixture stream; a supply chamber coupled to the reactor; a suction generator configured to generate a suction force at the outlet of the reactor; a fluid supply module configured to supply the conditioning fluid at an original pressure; and a pressure regulation module configured to: receive the conditioning fluid from the fluid supply module, reduce the pressure of the conditioning fluid from the original pressure to a selected pressure relative to the ambient pressure regardless of any changes in the suction force at the outlet of the reactor, and supply the conditioning fluid at the selected pressure to the supply chamber.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority to U.S. Provisional ApplicationSer. No. 60/928,946, filed May 11, 2007, entitled “MATERIAL PRODUCTIONSYSTEM AND METHOD,” which is hereby incorporated by reference as if setforth herein. The co-pending U.S. patent application Ser. No.11/110,341, filed on Apr. 10, 2005, entitled, “HIGH THROUGHPUT DISCOVERYOF MATERIALS THROUGH VAPOR PHASE SYNTHESIS” is incorporated byreference.

FIELD OF THE INVENTION

The present invention relates to systems for and methods of providing aconstant overpressure gas to a system with varying internal pressure.

BACKGROUND OF THE INVENTION

Some particle production systems rely on vacuum suction forces to carryparticle-containing mixtures from a reactor region to a collectionregion. However, when using such systems, care must be taken to produceor condition sensitive or reactive materials.

When operating in an ambient pressure environment, contamination mayoccur if the internal pressure of the system falls below the ambientpressure. One solution that can be effective is to seal the system.However, completely airtight seals, if available, are very expensive.

Often, less costly seals can be used if pressure within the system ismaintained at a level above the ambient pressure. However, too large adifferential between the system pressure and the ambient pressure canencourage leakage out of the system, which is also undesirable. Thus,the pressure differential should be minimized.

Unfortunately, in systems where the vacuum suction used is not constant,providing a fixed overpressure into the system will not effectivelyminimize the pressure differential between the system pressure and theambient pressure.

What is needed is a system and a method capable of sufficientlyminimizing the pressure differential in a system having a varying vacuumsuction.

SUMMARY OF THE INVENTION

In one aspect of the present invention, a system operating in anenvironment having an ambient pressure is provided. The system comprisesa reactor, a supply chamber, a suction generator, a conditioning fluidsupply module, and a pressure regulation module. The reactor has aworking gas inlet, a conditioning fluid inlet, a powder supply port, anda mixture outlet. The reactor is configured to receive a working gasthrough the working gas inlet, energize the working gas to form a plasmastream, receive powder particles through the powder supply port, receivethe conditioning fluid through the conditioning fluid inlet, combine theplasma stream, the powder particles and the conditioning fluid, therebyaltering the powder particles and forming a mixture stream, and supplythe mixture stream to the mixture outlet. The altered powder particlesare entrained within the mixture stream. The supply chamber is in fluidcommunication with the reactor through the conditioning fluid inlet. Thesuction generator is fluidly coupled to the reactor and configured togenerate a suction force at the mixture outlet of the reactor. Theconditioning fluid supply module is configured to supply theconditioning fluid at an original pressure. The pressure regulationmodule is fluidly coupled between the conditioning fluid supply moduleand the supply chamber. The pressure regulation module is configured to:receive the conditioning fluid at the original pressure from theconditioning fluid supply module, reduce the pressure of theconditioning fluid from the original pressure to a selected pressurerelative to the ambient pressure, wherein the pressure regulation moduleis configured to maintain the reduction of the conditioning fluidpressure to the same selected pressure regardless of any changes in thesuction force at the mixture outlet of the reactor, and supply theconditioning fluid at the selected pressure to the supply chamber.

In another aspect of the present invention, a method of supplying anoverpressure gas to a particle production reactor operating in anenvironment having an ambient pressure is provided. The reactor has aworking gas inlet, a conditioning fluid inlet, a powder supply inlet,and a mixture outlet. A suction generator provides a varying suction atthe mixture outlet of the particle production reactor. A pressureregulation module receives a conditioning fluid at an original pressurefrom a conditioning fluid supply module. The pressure regulation modulereduces the pressure of the conditioning fluid from the originalpressure to a selected pressure relative to the ambient pressure,wherein the pressure regulation module maintains the reduction of theconditioning fluid pressure to the same selected pressure regardless ofany changes in the suction force at the mixture outlet of the reactor. Asupply chamber receives the conditioning fluid at the selected pressurefrom the pressure regulation module, wherein the supply chamber isfluidly coupled to the conditioning fluid inlet of the particleproduction reactor. The particle production reactor receives a workinggas through the working gas inlet. The particle production reactorenergizes the working gas to form a plasma stream. The particleproduction reactor receives powder particles through the powder supplyport. The particle production reactor receives the conditioning fluidfrom the supply chamber through the conditioning fluid inlet. Theparticle production chamber combining the plasma stream, the powderparticles and the conditioning fluid, thereby altering the powderparticles and forming a mixture stream. The altered powder particles areentrained within the mixture stream. The mixture stream flows to themixture outlet of the particle production reactor.

In preferred embodiments, the conditioning fluid supply module comprisesa conditioning fluid reservoir and an evaporator. The conditioning fluidreservoir stores the conditioning fluid as a liquid gas. The evaporatorreceives the conditioning fluid as a liquid gas from the conditioningfluid reservoir. The evaporator then evaporates the conditioning fluidto produce the conditioning fluid in gaseous form. The pressureregulation module receives the conditioning fluid from the evaporator atthe original pressure in gaseous form.

In some embodiments, the conditioning fluid supply module comprises afirst conditioning fluid reservoir, a second conditioning fluidreservoir, a mixing valve, and an evaporator. The first conditioningfluid reservoir stores a first conditioning fluid as a liquid gas. Thesecond conditioning fluid reservoir stores a second conditioning fluidas a liquid gas. The mixing valve receives the first conditioning fluidas a liquid gas from the first conditioning fluid reservoir and thesecond conditioning fluid as a liquid gas from the second conditioningfluid reservoir. The mixing valve then mixes the first conditioningfluid and the second conditioning fluid to form the conditioning fluidas a liquid gas. The evaporator then receives the conditioning fluid asa liquid gas from the mixing valve and evaporates the conditioning fluidto produce the conditioning fluid in gaseous form. The pressureregulation module then receives the conditioning fluid from theevaporator at the original pressure in gaseous form.

Preferably, the pressure regulation module comprises a pressureregulator fluidly coupled between the conditioning fluid supply moduleand the supply chamber. In some embodiments, the pressure regulator is adiaphragm-based pressure regulator.

In preferred embodiments, the pressure regulation module furthercomprises a pressure relief module fluidly coupled between the pressureregulator and the supply chamber. The pressure relief module receivesthe conditioning fluid from the pressure regulator and vents a portionof the conditioning fluid to the environment, thereby reducing thepressure of the conditioning fluid prior to entry into the supplychamber.

The pressure regulation module preferably comprises a plurality ofpressure regulators fluidly coupled in serial formation between theconditioning fluid supply module and the supply chamber. Each one of theplurality of pressure regulators can be a diaphragm-based pressureregulator. In preferred embodiments, the plurality of pressureregulators comprises a first pressure regulator, a second pressureregulator, and a third pressure regulator. The first pressure regulatorreceives the conditioning fluid from the conditioning fluid supplymodule at the original pressure and reduces the pressure of theconditioning fluid from the original pressure to a second pressure. Thesecond pressure regulator receives the conditioning fluid from the firstpressure regulator at the second pressure and reduces the pressure ofthe conditioning fluid from the second pressure to a third pressure. Thethird pressure regulator receives the conditioning fluid from the secondpressure regulator at the third pressure and reduces the pressure of theconditioning fluid from the third pressure to a fourth pressure.

In preferred embodiments, the reactor comprises a plasma torch and areaction chamber. The plasma torch comprises the working gas inlet and aplasma outlet. The reaction chamber is fluidly coupled to the plasmaoutlet and comprises the conditioning fluid inlet, the powder supplyport and the mixture outlet. The plasma torch receives the working gasthrough the working gas inlet and energizes the working gas to form theplasma stream. The plasma torch then supplies the plasma stream to theplasma outlet. The reaction chamber receives the plasma stream throughthe plasma outlet, receives the powder particles through powder supplyport, and receives the conditioning fluid through the conditioning fluidinlet. The reaction chamber combines the plasma stream, the powderparticles and the conditioning fluid to form the mixture stream. Thereaction chamber then supplies the mixture stream to the mixture outlet.

In preferred embodiments, a collection system is fluidly coupled betweenthe mixture outlet of the reaction chamber and the suction generator.The collection system receives the mixture stream from the reactionchamber. The collection system then separates and collects the alteredpowder particles from the mixture stream. Preferably, the collectionsystem is fluidly coupled to the pressure regulation module receives theconditioning fluid at the selected pressure from the pressure regulationmodule.

In some embodiments, the step of combining the plasma stream, the powderparticles and the conditioning fluid to alter the powder particles andform the mixture stream comprises the steps of the particle productionreactor vaporizing the powder particles with the plasma stream and theparticle production chamber condensing the vaporized powder particles.

In some embodiments, the conditioning fluid is argon. Furthermore, theselected pressure at which the pressure regulation module provides theconditioning fluid is preferably equal to or less than 498 Pascals (2inches of water) relative to the ambient pressure, sufficientlyminimizing the pressure differential in the system, while stillproviding a constant overpressure regardless of any variation in suctionforce at the reactor outlet.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of one embodiment of a gas supplysystem integrated into a particle production system with varyinginternal pressure in accordance with the principles of the presentinvention.

FIG. 2 is a schematic illustration of one embodiment of a particleprocessing system supplied by a gas delivery system in accordance withthe principles of the present invention.

FIG. 3 is a schematic illustration of one embodiment of a particleproduction system supplied by a gas delivery system in accordance withthe principles of the present invention.

FIG. 4 is a schematic illustration of one embodiment of a gas reservoirfor use in a powder processing system in accordance with the principlesof the present invention.

FIG. 5 is a schematic illustration of one embodiment of a conditioninggas supply system for use in a powder processing system in accordancewith the principles of the present invention.

FIG. 6 is a flowchart illustrating one embodiment of a method ofproviding a constant overpressure gas to a system with varying internalpressure in accordance with the principles of the present invention.

FIG. 7 is a schematic illustration of one embodiment of a samplingstructure in a particle processing system supplied in accordance withthe principles of the present invention.

FIG. 8 is a schematic illustration of one embodiment of a samplingstructure in a particle processing system supplied in accordance withthe principles of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The description below concerns several embodiments of the invention. Thediscussion references the illustrated preferred embodiment. However, thescope of the present invention is not limited to either the illustratedembodiment, nor is it limited to those discussed, to the contrary, thescope should be interpreted as broadly as possible based on the languageof the Claims section of this document.

In the following description, numerous details and alternatives are setforth for purpose of explanation. However, one of ordinary skill in theart will realize that the invention can be practiced without the use ofthese specific details. In other instances, well-known structures anddevices are shown in block diagram form in order not to obscure thedescription of the invention with unnecessary detail.

This disclosure refers to both particles and powders. These two termsare equivalent, except for the caveat that a singular “powder” refers toa collection of particles. The present invention may apply to a widevariety of powders and particles. Powders that fall within the scope ofthe present invention may include, but are not limited to, any of thefollowing: (a) nano-structured powders (nano-powders), having an averagegrain size less than 250 nanometers and an aspect ratio between one andone million; (b) submicron powders, having an average grain size lessthan 1 micron and an aspect ratio between one and one million; (c)ultra-fine powders, having an average grain size less than 100 micronsand an aspect ratio between one and one million; and (d) fine powders,having an average grain size less than 500 microns and an aspect ratiobetween one and one million.

A wide variety of material types and forms can be processed inpreferable particle production reactors used in the present invention.Without prejudice, the present invention specifically considers theprovision of materials in the following forms: solid, liquid and gas.

An exemplary particle production system is a plasma powder productionreactor, which is included within several of the exemplary embodimentsdiscussed below. Generally, the plasma powder production reactorproduces an output comprising particles entrained within a gas stream.Particle production preferably includes the steps of combination,reaction, and conditioning. The present invention can employ conceptssimilar to those used in the nano-powder production systems disclosed inrelated U.S. patent application Ser. No. 11/110,341, filed on Apr. 19,2005 and entitled, “HIGH THROUGHPUT DISCOVERY OF MATERIALS THROUGH VAPORPHASE SYNTHESIS”, which is currently published as U.S. Publication No.2005-0233380-A. In such nano-powder production systems, working gas issupplied from a gas source to a plasma reactor. Within the plasmareactor, energy is delivered to the working gas, thereby creating aplasma. A variety of different means can be employed to deliver thisenergy, including, but not limited to, DC coupling, capacitive coupling,inductive coupling, and resonant coupling. One or more materialdispensing devices introduce at least one material, preferably in powderform, into the plasma reactor. The combination within the plasma reactorof the plasma and the material(s) introduced by the material dispensingdevice(s) forms a highly reactive and energetic mixture, wherein thepowder can be vaporized. This mixture of vaporized powder moves throughthe plasma reactor in the flow direction of the working gas. As itmoves, the mixture cools and particles are formed therein. Thestill-energetic output mixture, comprising hot gas and energeticparticles, is emitted from the plasma reactor.

Referring now to FIG. 1, a gas supply system 100 is configured todeliver gas to a particle production (or processing) system 170 havingvarying internal pressure. The particle production system 170 includes asupply chamber 172 that is fluidly coupled to a suction generator 174,such as a vacuum pump, preferably through a conduit.

In a preferred embodiment, the gas supply system 100 includes a fluid(preferably gas) reservoir 110 fluidly coupled to an evaporator 120,which is in turn fluidly coupled to a pressure regulation module. Thepressure regulation module preferably comprises a plurality of pressureregulators. In FIG. 1, the pressure regulation module comprises pressureregulators 130, 140, and 150 fluidly coupled together in serialformation. The outlet of the pressure regulation module is fluidlycoupled with the supply chamber 172. In a preferred embodiment, at leastone of the pressure regulators 130, 140, and 150 uses a diaphragm-basedregulation mechanism. Preferably, the diaphragm-based regulationmechanism comprises a diaphragm-based demand valve.

The pressure regulation module can further include a pressure reliefmodule 160 fluidly coupled between the pressure regulators and thesupply chamber 172. The pressure relief module 160 preferably includespressure relief valves 162 and 164. Pressure relief valves 162 and 164are each independently coupled between the outlet of the pressureregulators and an inlet of the supply chamber 172. The pressure reliefmodule 160 is configured to vent gas to the ambient environment.

The pressure regulation module is configured to receive a fluid(preferably a gas) having an original pressure and to reduce thepressure of the fluid from the original pressure to a selected pressurerelative to the ambient pressure. The pressure regulation module isconfigured to maintain the reduction of the fluid pressure to theselected pressure regardless of any changes in the suction forcegenerated by the suction generator 174 so that the fluid is provided tothe supply chamber 172 at that same selected pressure whether thesuction force increases, decreases or stays the same.

In a preferred operation of the system 100, the fluid reservoir 110supplies liquefied gas (such as liquid argon) at pressure P₀ (such asapproximately 360 PSI) to the evaporator 120. The evaporator 120evaporates the liquefied gas to form a gas at pressure P₁ (such asapproximately 300 PSI), which it supplies to the pressure regulationmodule. The pressures P₀ and P₁ are selected by configuring thereservoir 110 and evaporator 120. Typically, these pressures are muchhigher than the ambient pressure in which the system 100 operates.However both P₁ and P₀ are typically not directly dependent on theambient pressure.

The pressure regulation module reduces the gas pressure from P₁ to anoutlet pressure P₄, which is set relative to ambient pressure. Thepressure regulation module controls pressure of the gas supplied to thesupply chamber 172 to have a fixed pressure relative to the ambient,regardless of demand. In some embodiments, the outlet pressure P₄ is afixed amount greater than the ambient pressure. In some embodiments, theoutlet pressure P₄ has a fixed ratio relative to the ambient pressure.Typically, the specific relationship between the ambient pressure and P₄depends on the configuration of the pressure regulation module.Preferably, P₄ is set only a slight amount above ambient pressure. In apreferred embodiment, the pressure regulation module reduces the gaspressure to approximately equal to or less than 498 Pascals (2 inches ofwater) relative to the ambient pressure. Preferably, the pressure isreduced to approximately 249 Pascals (1 inch of water) relative to theatmospheric pressure.

The pressure relief module 160 receives gas at pressure P₄. If P₄ isabove a selected threshold, the pressure relief module 160 vents gas tothe ambient environment, reducing the inlet pressure to the supplychamber 172. Preferably, the threshold is selected to be relatively highcompared to ambient, so that under normal operation the pressure reliefmodule 160 is not activated. As mentioned above, the pressure reliefmodule 160 preferably comprises a plurality of pressure relief valves.As illustrated, the pressure relief module 160 includes a first pressurerelief valve 162 and a second pressure relief valve 164. In someembodiments, the first pressure relief valve 162 and the second pressurerelief valve 164 have differing sensitivities and are set at differingthresholds.

Referring back to the preferred operation, the first pressure regulator130 receives the gas from the evaporator 120 at the inlet pressure P₁(such as approximately 300 PSI) and outputs the gas at a reduced outletpressure P₂ (such as approximately 50 PSI). Typically, the firstpressure regulator 130 includes a control portion 134 and a valveportion 132. Control portion 134 uses input from P₁ and/or ambientpressure in determining the outlet pressure P₂.

The second pressure regulator 140 receives gas at the outlet pressure P₂from the first pressure regulator 130 and outputs gas at a reducedoutlet pressure P₃ (such as approximately 2 PSI). Typically, the secondpressure regulator 140 includes a control portion 144 and a valveportion 142. Control portion 144 uses input from P₂ and/or ambientpressure in determining the outlet pressure P₃.

The third pressure regulator 150 receives gas at the outlet pressure P₃from the second pressure regulator 140 and outputs gas at a reducedoutlet pressure P₄ (such as approximately 249 Pascals (1 inch of water)relative to ambient pressure). Typically, the third pressure regulator150 includes a control portion 154 and a valve portion 152. Controlportion 154 uses input from P₃ and/or ambient pressure in determiningthe outlet pressure P₄.

In accordance with the present invention, embodiments of supply systemssuch as the one above are integrated into a variety of particleproduction or processing systems having varying vacuum loads. Someembodiments of the systems contemplated within the present invention aredescribed below with reference to FIGS. 2 and 3.

Referring now to FIG. 2, an embodiment of a powder processing apparatus200 is presented. The powder processing apparatus 200 includes a plasmatorch 210, a gas supply chamber 215, a reaction chamber 250, a powderdispensing device 240, a conditioning gas supply system 230, a workinggas supply system 220, a collection system 260, and a suction generator270.

The plasma torch 210 is configured to receive a working gas from theworking gas supply system 220 at the working gas inlet 213. Preferably,the working gas consists of impurity-binding atoms and noble gas atomsin a selectable ratio. During operation, the plasma torch 210 formsplasma from the working gas, preferably by delivering energy to theworking gas.

The reaction chamber 250 defines a path from its input port 252 to itsoutput port 258. The input port 252 is coupled with the plasma torch 210and the output port 258 is coupled with the conduit system 280.Preferably, the plasma torch 210 is configured to deliver plasma intothe reaction chamber 250 through the input port 252. In a preferredembodiment, the reaction chamber 250 comprises a substantiallycylindrical portion extending away from the plasma torch 210 and into afrusto-conical portion, which comprises a wide end leading into a narrowend as it extends away from the plasma torch and into the output port258. The wide end of the reaction chamber 250 preferably has an annularsurface on which the input port 252 is disposed. The annular surfacepreferably has a large diameter relative to the size of the input port252 through which the plasma stream enters the reaction chamber 250 fromthe plasma torch 210, thereby providing accommodation for the expansionof the plasma stream that occurs after the plasma stream flows into thereaction chamber 250. In a preferred embodiment, the frusto-conicalsurface is sufficiently smoothly varying so as to not unduly compressfluid flowing through the reaction chamber 250 to the output port 258.

The powder-dispensing device 240 is fluidly coupled with the reactionchamber 250 through a supply channel 242 and a supply port 244. Thepowder-dispensing device 240 can supply powder through the supplychannel 242 to the supply port 244 and into the reaction chamber 250 ata selectable rate. Preferably, the supply channel 242 is configurable todeliver powder to a selectable location within the reaction chamber 250.

In a preferred embodiment, the reaction chamber 250 is fluidly coupledto the collection system 260 and the suction generator 270 via theconduit system 280. The suction generator 270 is configured to generatea suction force at the output port 258. The conduit system 280 isconfigured to receive a mixture stream from the reaction chamber 250through the output port 258.

The gas supply chamber 215 is fluidly coupled to the reaction chamber250, preferably through one or more inlets 254. In this respect, the gassupply chamber 215 can supply a fluid, such as a conditioning fluid,into the reaction chamber 250.

The conditioning gas supply system 230 is configured to deliverconditioning gas into the gas supply chamber 215 and to the collectionsystem 260 at a selected pressure relative to ambient. In this respect,the conditioning gas supply system 230 can incorporate the pressureregulation module discussed above, as well as the fluid reservoir andthe evaporator. As previously mentioned, the gas supply chamber 215 isfluidly coupled to the reaction chamber 250 and the collection system260 is fluidly coupled to the conduit system 280. Preferably, theconditioning gas supply system 230 supplies conditioning gas to both thereaction chamber 250 and the collection system 260 at a constantpressure relative to ambient regardless of the demand from the suctiongenerator 270. Alternatively, a separate, but similar, conditioning gassupply system supplies conditioning gas to the collection system 260. Inthe alternative embodiment, the two conditioning gas supply systemspreferably supply the same pressure and contain the same type ofconditioning gas. However, either the overpressure or the type of thegas supplied can vary between the two conditioning gas supply systems.The apparatus 200 can further comprise a reducing gas supply system 290fluidly coupled through a gas supply port 292 into the reaction chamber250.

Additionally, the apparatus 200 can comprise getter pumps 282 and 284,respectively configured at the output port 258 of the reaction chamber250 and within the conduit 280 proximate to the collection system 260.Furthermore, the apparatus 200 can also comprise a temperature controlsystem 286 that is coupled to a portion of the conduit system 280 and/orto a portion of the reaction chamber 250 and that is configured tocontrol the temperature of the portion of the conduit system 280 and/orthe reaction chamber 250.

In a preferred operation of the apparatus 200, the plasma torch 210receives a working gas, such as a mixture of hydrogen and argon, fromthe working gas supply system 220 and delivers energy to the workinggas, thereby forming a plasma stream. The suction generator 270generates a suction force at the output port 258. The reaction chamber250 receives powder from the powder dispensing device 240, conditioninggas from the conditioning gas supply system 230 through the supplychamber 215, and the plasma stream from the plasma torch 210. Asdiscussed above, the pressure regulation module of the conditioning gassupply system 230 provides the conditioning gas to the supply chamber215 at a selected pressure (preferably slightly above ambient pressure)regardless of any variation in the suction force at the output port 258.

The powder, conditioning gas, and the plasma stream mix within thereaction chamber, preferably altering the powder and forming a mixturestream within the reaction chamber 250. The mixture stream preferablycomprises the altered powder entrained within the mixture stream. Themixture stream is forced through the output port 258 and through thecollection system 260 by the suction generator 270.

The reducing gas supply system 290 preferably supplies reducing gas intothe reaction chamber 250 through the supply channel 292. Preferably, thesupply channel 292 is moveable to deliver reducing gas to a selectablelocation within the reaction chamber 250. Furthermore, the reducing gassupply system 290 preferably supplies reducing gas at a selectable rate.During operation, the reducing gas serves to flood a selectable portionof the reaction chamber 250 with reducing gas, to promote reduction andcool material within that region. For example, a location correspondingto a particular portion of a plasma plume can be flooded to takeadvantage of high temperatures that permit fast reduction reactions.

The getter pumps 282 and 284 are positioned to absorb impuritiesliberated from the powder during processing and prevent them from beingreincorporated into the powder during cooling. During operation, as apowder is introduced into the reaction chamber 250, its particlesencounter hot gasses and plasmas. The heating of the powder separatescertain impurities from the particles of the powder. These impuritiescan remain separated, or later recombine as the particles and the gascool. The getter pumps 282 are positioned to retain these impurities andprevent them from reuniting with the particles of the powder. Fartheralong in the conduit system 280, the getter pumps 284 are positioned toretain the liberated impurities and any other impurities that may formduring the cooling of the mixture as it moves from the reaction chamber250 through the conduit system 280.

The temperature control system 286 is configured to control thetemperature of the walls of the conduit system 280 between the reactionchamber 250 and the collection system 260. Furthermore, the temperaturecontrol system 286 can also control the temperature of some of the wallsof the reaction chamber 250. Preferably, the temperature of the walls iscontrolled to minimize contamination of the conduit system 280 and ofthe reaction chamber 250 (e.g., particle deposition). In an alternativeembodiment, the interior surface of the conduit system 280 is coated tominimize contamination. Of course, it is contemplated that coatings andtemperature control can be used in concert.

The mixture stream preferably flows from the conduit system 280 throughthe collection system 260. The collection system 260 separates andcollects powder particles from the mixture stream, allowing rest of themixture stream to flow through towards the suction generator 270. Thecollection system 260 preferably permits the suction generator 270 toprovide a motive force there-through. However, in some embodiments thecollection system 260 provides additional motive force. The collectionsystem 260 is preferably configured to separate a portion of theparticles transported within the mixture stream from the main body ofthe stream and to allow removal and analysis of the particles.Furthermore, the collection system 260 can take multiple samples, atselected times, and can sample discontinuously, which allows forsampling from gas-particle streams whose composition may vary from timeto time without contamination from previous product.

It is contemplated that the collection system 260 can be configured in avariety of ways. In one embodiment, as shown in FIG. 7, the collectionsystem 260 comprises a sampling structure 720, at least one filledaperture 754 formed in the sampling structure 720, and at least oneunfilled aperture 752 formed in the sampling structure 720. Each filledaperture 754 is configured to collect particles from the mixture stream,such as by using a filter 740. The sampling structure 720 is configuredto be adjusted between a pass-through configuration and a collectionconfiguration. The pass-through configuration comprises an unfilledaperture 752 being fluidly aligned with a conduit, such as the conduitsystem 780, thereby allowing the unfilled aperture 752 to receive themixture stream from the conduit 780 and the mixture stream to flowthrough the sampling structure 720 without substantially altering theparticle content of the mixture stream. The collection configurationcomprises a filled aperture 754 being fluidly aligned with the conduit780, thereby allowing the filled aperture 754 to receive the mixturestream and collect particles while the mixture stream is being flownthrough the filled aperture 754.

It is contemplated that the sampling structure 720 can be adjustedbetween the pass-through configuration and the collection configurationin a variety of ways. In one embodiment, the sampling structure is adisk-shaped structure 722 including an annular array of apertures,wherein the annular array comprises a plurality of the filled apertures754 and a plurality of the unfilled apertures 752. The samplingstructure 720 is rotatably mounted to a base 760, wherein rotationalmovement of the sampling structure 720 results in the adjustment of thesampling structure 720 between the pass-through configuration and thecollection configuration. In another embodiment, shown in FIG. 8, thesampling structure 820 is a rectangular-shaped structure including alinear array of apertures 850, wherein the linear array comprises aplurality of the filled apertures 854 and a plurality of the unfilledapertures 852. As in FIG. 7, discussed above, filled apertures comprisea filter 848 to collect particles from the mixture stream flowingthrough the sampling structure 820 from the conduit system 880. Thesampling structure 820 is slideably mounted 810 to a base 860, whereinsliding of the sampling structure 820 results in the adjustment of thesampling structure 820 between the pass-through configuration and thecollection configuration.

FIG. 3 is a schematic illustration of one embodiment of a particleproduction system 300 supplied by a gas delivery system in accordancewith the principles of the present invention. The powder productionsystem 300 is similar to the system 200 of FIG. 2 and includes a plasmatorch 310, a gas supply chamber 315, a reaction chamber 350, a powderdispensing device 340, a conditioning gas supply system 330, a workinggas supply system 320, a collection system 360, and a suction generator370.

The plasma torch 310 is configured to receive a working gas from theworking gas supply system 320 at the working gas inlet 313. Preferably,the working gas consists of impurity-binding atoms and noble gas atomsin a selectable ratio. During operation, the plasma torch 310 formsplasma from the working gas, preferably by delivering energy to theworking gas.

The reaction chamber 350 defines a path from its input port 352 to itsoutput port 358. The input port 352 is coupled with the plasma torch 310and the output port 358 is coupled with the conduit system 380.Preferably, the plasma torch 310 is configured to deliver plasma intothe reaction chamber 350 through the input port 352. In a preferredembodiment, the reaction chamber 350 comprises a substantiallycylindrical portion extending away from the plasma torch 310 and into afrusto-conical portion, which comprises a wide end leading into a narrowend as it extends away from the plasma torch and into the output port358. The wide end of the reaction chamber 350 preferably has an annularsurface on which the input port 352 is disposed. The annular surfacepreferably has a large diameter relative to the size of the input port352 through which the plasma stream enters the reaction chamber 350 fromthe plasma torch 310, thereby providing accommodation for the expansionof the plasma stream that occurs after the plasma stream flows into thereaction chamber 350. In a preferred embodiment, the frusto-conicalsurface is sufficiently smoothly varying so as to not unduly compressfluid flowing through the reaction chamber 350 to the output port 358.

The powder-dispensing device 340 is fluidly coupled with the plasmatorch 310 through a supply channel 342, thereby allowing the powder toflow into the plasma torch, as opposed to the powder flowing directlyinto the reaction chamber as in FIG. 2. The powder-dispensing device 340can supply powder at a selectable rate. Preferably, the supply channel342 is configurable to deliver powder to a selectable location withinthe plasma torch 310.

In a preferred embodiment, the reaction chamber 350 is fluidly coupledto the collection system 360 and the suction generator 370 via theconduit system 380. The suction generator 370 is configured to generatea suction force at the output port 358. The conduit system 380 isconfigured to receive a mixture stream from the reaction chamber 350through the output port 358.

The gas supply chamber 315 is fluidly coupled to the reaction chamber350, preferably through one or more inlets 354. In this respect, the gassupply chamber 315 can supply a fluid, such as a conditioning fluid,into the reaction chamber 350.

The conditioning gas supply system 330 is configured to deliverconditioning gas into the gas supply chamber 315 and to the collectionsystem 360 at a selected pressure relative to ambient. In this respect,the conditioning gas supply system 330 can incorporate the pressureregulation module discussed above, as well as the fluid reservoir andthe evaporator. As previously mentioned, the gas supply chamber 315 isfluidly coupled to the reaction chamber 350 and the collection system360 is fluidly coupled to the conduit system 380. Preferably, theconditioning gas supply system 330 supplies conditioning gas to both thereaction chamber 350 and the collection system 360 at a constantpressure relative to ambient regardless of the demand from the suctiongenerator 370. Alternatively, a separate, but similar, conditioning gassupply system supplies conditioning gas to the collection system 360. Inthe alternative embodiment, the two conditioning gas supply systemspreferably supply the same pressure and contain the same type ofconditioning gas. However, either the overpressure or the type of thegas supplied can vary between the two conditioning gas supply systems.

Additionally, the apparatus 300 can comprise getter pumps and/or atemperature control system, such as those discussed with respect to FIG.2.

In a preferred operation of the system 300, the plasma torch 310receives a working gas, such as a mixture of hydrogen and argon, fromthe working gas supply system 320 and receives powder from the powderdispensing device 340. The plasma torch 310 delivers energy to theworking gas, thereby forming a plasma stream. The plasma stream isapplied to the powder within the plasma torch, thereby altering thepowder and forming a mixture stream within which the altered powder isentrained. In a preferred embodiment, the plasma stream vaporizes thepowder.

The suction generator 370 generates a suction force at the output port358. The reaction chamber 350 receives conditioning gas from theconditioning gas supply system 330 through the supply chamber 315, andthe mixture stream from the plasma torch 310. As discussed above, thepressure regulation module of the conditioning gas supply system 330provides the conditioning gas to the supply chamber 315 at a selectedpressure (preferably slightly above ambient pressure) regardless of anyvariation in the suction force at the output port 358. Within thereaction chamber 350, the species within the mixture stream suppliedfrom the plasma torch 310 condense to form particles.

The conditioning gas mixes with the mixture stream within the reactionchamber 350. In certain embodiments, the conditioning fluid serves tocool the mixture stream. The mixture stream is then forced through theoutput port 358 and through the collection system 360 to the collectionsystem 360 by the suction generator 370. The collection system 360 canhave all of the same features as collection system 260 discussed abovewith respect to FIG. 2.

Fluid reservoirs used within some embodiments of the present inventioncan be configured to supply a mixture of fluids. Referring now to FIG.4, a mixed gas reservoir system 400 for use in the certain embodimentsof the fluid supply systems of the present invention is discussed. Thereservoir system 400 includes a first gas reservoir 410 containing afirst gas and a second gas reservoir 420 containing a second gas. Thefirst gas reservoir 410 and the second gas reservoir 420 are fluidlycoupled through regulators 415 and 425, respectively, to a mixing valve430 and an output conduit 440. During operation, tuning of theregulators 415 and 425 along with the mixing valve 430 can produce adesired ratio of the first gas and the second gas. It is contemplatedthat these reservoirs can store and supply fluid in gaseous form or as aliquified gas.

Referring now to FIG. 5, a conditioning gas supply system 500 isdisclosed for use in a powder processing or production system, such asthose discussed above. The conditioning gas supply system 500 is capableof supplying conditioning gas, whether in gaseous form or as a liquifiedgas, to a supply chamber at a substantially constant pressure relativeto a range of different suction conditions within the chamber. Theconditioning gas supply system 500 includes conditioning gas reservoirs510 fluidly coupled through a manifold 515 to an evaporator 520, such asthe evaporator 120 of FIG. 2. The evaporator 520 is fluidly coupled to apressure regulation module 530, such as the pressure regulation modulediscussed with respect to FIG. 1. During operation, gas supplied fromthe reservoirs 510 through the manifold 515 is evaporated in theevaporator 520, and then passed through the pressure regulation module530. The pressure regulated gas is then supplied from the pressureregulation module 530 into the supply chamber, where it can be used in apowder processing or production system as previously discussed. Thepressure regulation module 530 controls the pressure of the gas suppliedto the supply chamber, maintaining a fixed pressure relative to theambient pressure, regardless of demand. In some embodiments, the systemof FIG. 5 includes pressure regulation modules as outlined with respectto FIG. 1.

FIG. 6 illustrates one embodiment of a method 600 of supplying anoverpressure gas to a particle production system operating in anenvironment having an ambient pressure. The particle production systempreferably comprises a plasma torch having a working gas inlet and areactor chamber having a conditioning fluid inlet, a powder supply port,and a mixture outlet.

During a first period, the plasma torch produces a plasma stream at step610. In a preferred embodiment, the plasma torch receives a working gasthrough the working gas inlet, then energizes the working gas to formthe plasma stream. At step 620, the plasma stream flows into the reactorchamber. During the first period, a suction generator provides a firstsuction force at the mixture outlet of the reactor chamber at step 630a. At step 640, a gas supply module supplies conditioning fluid to apressure regulation module at an original pressure. In one embodiment,the conditioning fluid is pure argon. At step 650, the pressureregulation module reduces the pressure of the conditioning fluid fromthe original pressure to a selected pressure relative to the atmosphericpressure. It is contemplated that the selected pressure can comprise asmall range above the ambient pressure, such as equal to or less thanapproximately 498 Pascals (2 inches of water) over atmosphere, or can bea specific level, such as equal to approximately 249 Pascals (1 inch ofwater) over atmosphere. At step 660, the conditioning fluid flows fromthe pressure regulation module into the supply chamber, and optionallyto a collection system fluidly coupled downstream from the reactorchamber, at the selected pressure. The supply chamber is fluidly coupledto the conditioning fluid inlet of the reactor chamber. At step 670, thereactor chamber combines the plasma stream from the plasma torch, powderparticles from the powder supply port, and the conditioning fluid fromthe supply chamber, thereby altering the powder particles and forming amixture stream. It is contemplated that the powder particles can bedelivered into directly into the reactor chamber (as in FIG. 2) or canbe first delivered into the plasma torch (as in FIG. 3). The alteredpowder particles are entrained within the mixture stream. At step 680,the mixture stream flows to the mixture outlet of the reactor chamber.It can then flow to the rest of the system, such as the collectionsystem.

The pressure regulation module maintains the reduction of theconditioning fluid pressure to the same selected pressure regardless ofany changes in the suction force at the mixture outlet of the reactor.In this respect, the process can repeat itself during another perioddefined by a varied suction force and perform the same steps. As seen inFIG. 6, instead of the suction generator providing a first suction forceat step 630 a, the suction generator provides a second suction force atstep 630 b. Although the second suction force it different from thefirst suction force, the pressure regulation module still regulates thepressure of the conditioning fluid and supplies the conditioning fluidto the supply chamber at the same selected pressure, preferably at249-498 Pascals (1-2 inches of water) over atmosphere.

As would be appreciated by those of ordinary skill in the art, theprotocols, processes, and procedures described herein may be repeatedcontinuously or as often as necessary to satisfy the needs describedherein. Additionally, although the operations are shown or described ina specific order, certain steps may occur simultaneously or in adifferent order than illustrated. For example, the reactor can receivethe conditioning fluid before, during or after the period it receivesthe working gas and/or the powder. Accordingly, the operations of thepresent invention should not be limited to any particular order unlesseither explicitly or implicitly stated in the claims. In this respect,the use of letters as element headings (e.g., a), b), c), etc.) shouldnot be interpreted as limiting the scope of a claim to any particularorder other than that otherwise required by the actual claim language.

The present invention has been described in terms of specificembodiments incorporating details to facilitate the understanding of theprinciples of construction and operation of the invention. As such,references herein to specific embodiments and details thereof are notintended to limit the scope of the claims appended hereto. It will beapparent to those skilled in the art that modifications can be made tothe embodiments chosen for illustration without departing from thespirit and scope of the invention.

What is claimed is:
 1. A system operating in an environment having anambient pressure, the system comprising: a reactor comprising a plasmatorch and a reaction chamber, the plasma torch comprising a working gasinlet and a plasma outlet, and the reaction chamber fluidly coupled tothe plasma outlet and comprising a conditioning fluid inlet, a powdersupply port, and a mixture outlet, wherein: the plasma torch isconfigured to: receive the working gas through the working gas inlet,energize the working gas to form a plasma stream, and supply the plasmastream to the plasma outlet; the reaction chamber is configured to:receive the plasma stream through the plasma outlet, receive powderparticles through the powder supply port, receive a conditioning fluidthrough the conditioning fluid inlet, combine the plasma stream, thepowder particles and the conditioning fluid, thereby altering the powderparticles and forming a mixture stream, wherein the altered powderparticles are entrained within the mixture stream, and supply themixture stream to the mixture outlet; a supply chamber in fluidcommunication with the reactor through the conditioning fluid inlet; asuction generator fluidly coupled to the reactor and configured togenerate a suction force at the mixture outlet of the reactor; aconditioning fluid supply module configured to supply the conditioningfluid at an original pressure, higher than the ambient pressure in whichthe system is operating; and a pressure regulation module fluidlycoupled between the conditioning fluid supply module and the supplychamber and configured to: receive the conditioning fluid at theoriginal pressure from the conditioning fluid supply module, reduce thepressure of the conditioning fluid from the original pressure to aselected pressure relative to the ambient pressure, wherein the pressureregulation module is configured to maintain the reduction of theconditioning fluid pressure to the same selected pressure regardless ofany changes in the suction force at the mixture outlet of the reactor,and supply the conditioning fluid at the selected pressure to the supplychamber.
 2. The system of claim 1, wherein the conditioning fluid supplymodule comprises: a conditioning fluid reservoir configured to store andsupply the conditioning fluid in liquid form; and an evaporator fluidlycoupled between the conditioning fluid reservoir and the pressureregulation module and configured to receive the conditioning fluid inliquid form from the conditioning fluid reservoir, to evaporate theconditioning fluid, and to supply the conditioning fluid to the pressureregulation module at the original pressure in gaseous form.
 3. Thesystem of claim 1, wherein the conditioning fluid supply modulecomprises: a first conditioning fluid reservoir configured to store andsupply a first conditioning fluid as a liquid gas; a second conditioningfluid reservoir configured to store and supply a second conditioningfluid as a liquid gas; a mixing valve fluidly coupled to the first andsecond conditioning fluid reservoirs and configured to receive and mixthe first and second conditioning fluids to form a conditioning fluid asa liquid gas; and an evaporator fluidly coupled between the mixing valveand the pressure regulation module and configured to receive theconditioning fluid as a liquid gas from the mixing valve, to evaporatethe conditioning fluid, and to supply the conditioning fluid as a gas tothe pressure regulation module at the original pressure.
 4. The systemof claim 1, wherein the pressure regulation module comprises a pressureregulator fluidly coupled between the conditioning fluid supply moduleand the supply chamber.
 5. The system of claim 4, wherein the pressureregulator is a diaphragm-based pressure regulator.
 6. The system ofclaim 4, wherein the pressure regulation module further comprises apressure relief module fluidly coupled between the pressure regulatorand the supply chamber and configured to receive the conditioning fluidfrom the pressure regulator and to vent a portion of the conditioningfluid to the environment, thereby reducing the pressure of theconditioning fluid prior to entry into the supply chamber.
 7. The systemof claim 1, wherein the pressure regulation module comprises a pluralityof pressure regulators fluidly coupled in serial formation between theconditioning fluid supply module and the supply chamber.
 8. The systemof claim 7, wherein each one of the plurality of pressure regulators isa diaphragm-based pressure regulator.
 9. The system of claim 7, whereinthe plurality of pressure regulators comprises: a first pressureregulator configured to receive the conditioning fluid from theconditioning fluid supply module and to reduce the pressure of theconditioning fluid from the original pressure to a second pressure; asecond pressure regulator configured to receive the conditioning fluidfrom the first pressure regulator and to reduce the pressure of theconditioning fluid from the second pressure to a third pressure; and athird pressure regulator configured to receive the conditioning fluidfrom the second pressure regulator and to reduce the pressure of theconditioning fluid from the third pressure to a fourth pressure.
 10. Thesystem of claim 7, wherein the pressure regulation module furthercomprises a pressure relief module fluidly coupled between the pluralityof pressure regulators and the supply chamber and configured to receivethe conditioning fluid downstream from the plurality of pressureregulators and to vent a portion of the conditioning fluid to theenvironment, thereby reducing the pressure of the conditioning fluidprior to entry into the supply chamber.
 11. The system of claim 1,further comprising a collection system fluidly coupled between themixture outlet of the reaction chamber and the suction generator,wherein the collection system comprises a sampling structure having afilter configured to receive the mixture stream from the reactionchamber and to separate and collect the altered powder particles fromthe mixture stream.
 12. A system operating in an environment having anambient pressure, the system comprising: a reactor, a plasma torchcomprising a working gas inlet and a plasma outlet, a reaction chamberfluidly coupled to the plasma outlet and comprising a conditioning fluidinlet, a powder supply port, and a mixture outlet, wherein: a) theplasma torch is configured to: (i) receive the working gas through theworking gas inlet, (ii) energize the working gas to form a plasmastream, and (iii) supply the plasma stream to the plasma outlet; b) thereaction chamber is configured to: (i) receive the plasma stream throughthe plasma outlet, (ii) receive powder particles through the powdersupply port, (iii) receive a conditioning fluid through the conditioningfluid inlet, (iv) combine the plasma stream, the powder particles andthe conditioning fluid, thereby altering the powder particles andforming a mixture stream, wherein the altered powder particles areentrained within the mixture stream, and (v) supply the mixture streamto the mixture outlet; a supply chamber in fluid communication with thereactor through the conditioning fluid inlet; a suction generatorfluidly coupled to the reactor and configured to generate a suctionforce at the mixture outlet of the reactor; a conditioning fluid supplymodule configured to supply the conditioning fluid at an originalpressure, higher than the ambient pressure; and a pressure regulationmodule fluidly coupled between the conditioning fluid supply module andthe supply chamber and configured to: a) receive the conditioning fluidat the original pressure from the conditioning fluid supply module, b)reduce the pressure of the conditioning fluid from the original pressureto a selected pressure relative to the ambient pressure, wherein thepressure regulation module is configured to maintain the reduction ofthe conditioning fluid pressure to the same selected pressure regardlessof any changes in the suction force at the mixture outlet of thereactor, and c) supply the conditioning fluid at the selected pressureto the supply chamber; a collection system fluidly coupled between themixture outlet of the reaction chamber and the suction generator,wherein the collection system comprises a sampling structure configuredto receive the mixture stream from the reaction chamber and to separateand collect the altered powder particles from the mixture stream, andwherein the collection system is fluidly coupled to the pressureregulation module and is configured to receive the conditioning fluid atthe selected pressure from the pressure regulation module.
 13. Thesystem of claim 1, wherein the reactor altering the powder particlescomprises vaporizing the powder particles, then condensing the vaporizedpowder particles.
 14. The system of claim 9, wherein the first pressureregulator is configured to receive the conditioning fluid at 300 psi andis further configured to reduce the pressure of the conditioning fluidto 50 psi, the second pressure regulator is configured to receive theconditioning fluid at 50 psi and is further configured to reduce thepressure of the conditioning fluid to 2 psi, and the third pressureregulator is configured to receive the conditioning fluid at 2 psi andis further configured to reduce the pressure to 498 Pascals (2 inches ofwater).
 15. The system of claim 9, wherein the third pressure regulatorcomprises a demand valve.